Inherent Jurisdiction as the Only Lawful Route for Deprivation of Liberty and Contact Restrictions Not Permissible Under the Assisted Decision‑Making (Capacity) Act 2015: Commentary on HSE v M.T. [2025] IEHC 440

Introduction

In Health Service Executive v M.T. [2025] IEHC 440, O’Donnell J of the High Court (Ireland) delivered a detailed judgment that both resolves a difficult protection case for a vulnerable adult and sets out important legal principles at the intersection of the Court’s inherent constitutional jurisdiction and the Assisted Decision‑Making (Capacity) Act 2015 (the 2015 Act).

The central issue was whether, and in what manner, the High Court may impose “light‑touch” but still liberty‑restrictive safeguarding measures for a vulnerable adult who lacks decision‑making capacity, where:

• there is no mental disorder within the Mental Health Act 2001;
• there is no intellectual disability;
• capacity deficits arise from profound environmental deprivation and maladaptive learned behaviours; and
• the protective measures needed (including contingent deprivation of liberty and restrictions on contact with family/internet) cannot lawfully be made under the 2015 Act.

Against a very sensitive factual background—extreme squalor in the family home, significant self‑neglect, and a marked divergence between average intellect and extremely low adaptive functioning—the HSE sought continuation of limited safeguarding orders. The guardian ad litem (GAL) opposed resort to the inherent jurisdiction on the basis that the 2015 Act could accommodate the necessary supports. The Court’s answer has wide systemic significance: while the 2015 Act is the primary vehicle for facilitating decision‑making, it neither authorises deprivation of liberty in this context nor permits prohibitions on contact. Where such measures are necessary and proportionate, they must proceed—sparingly—under the High Court’s inherent constitutional jurisdiction, with robust safeguards and with the guiding principles of the 2015 Act informing the Court’s approach.

Summary of the Judgment

The Court:

• Made detailed findings of fact that the family home was in a state of “remarkable squalor” and uninhabitable; that the respondent, M.T., presented with severe self‑neglect; and that these conditions long predated the intervention.
• Accepted the consensus clinical evidence that M.T.:
  • has average cognitive ability but extremely low adaptive functioning (functionally within the disability range);
  • lacks decision‑making capacity in respect of residence, personal safety and welfare, management of finances (at least for larger transactions), and contact/internet use; and
  • does not have a mental disorder within the 2001 Act and does not have an intellectual disability; her capacity impairment arises from environmental deprivation and maladaptive learned behaviours (with features described by experts as consistent with dependent traits/trauma bonding/Stockholm‑type phenomena).
• Found that although the orders sought were “light‑touch,” the Garda power to return M.T. to her placement amounts to deprivation of liberty/detention in law.
• Held that:
  • The 2015 Act cannot authorise detention in this context (save for limited Part 10 scenarios not applicable here);
  • Section 44(1) of the 2015 Act expressly prohibits conferring on a decision‑making representative the power to prohibit a person having contact with the relevant person; and
  • Section 38 does not enable the Circuit Court to do, in urgent form, what Part 5 elsewhere expressly forbids (i.e., it cannot be read to override s. 44).
• Concluded that the only lawful route for the necessary (and proportionate) deprivation of liberty and contact restrictions is the High Court’s inherent constitutional jurisdiction, expressly preserved by s. 4(5) of the 2015 Act.
• Continued the existing protective orders with modifications:
  • Designated the supported placement as M.T.’s residence;
  • Permitted the person‑in‑charge to regulate outings, visitors, and contact; and regulate/restrict internet and phone use;
  • Authorised Garda return powers if M.T. absconds;
  • Directed the HSE and GAL to explore technological solutions that may allow safe, supervised phone/internet access (to minimise restriction);
  • Listed the matter for regular reviews, with fresh evidence required to continue orders; and
  • Reserved the question of financial protection orders and indicated a provisional costs ruling in favour of the respondent/GAL against the HSE.
• Clarified the GAL’s role post‑Martinez Fernandez v Hungary (ECtHR, 2025): Irish GALs must both convey the person’s will and preferences and test the evidence, and may, where appropriate, offer an objective best‑interests‑type appraisal without abandoning the person’s voice.

Analysis

Precedents Cited and Their Influence

• Kirwan v Connors [2025] IESC 21: The Supreme Court distinguishes between the High Court’s inherent subject‑matter jurisdiction (constitutional, “full original jurisdiction”) and inherent procedural powers. O’Donnell J relies on this to explain why cautions in G. McG v DW (No. 2) and Mavior v Zerko about inherent powers do not constrain the High Court’s inherent constitutional jurisdiction to protect fundamental rights (especially under Article 40.3).
• HSE v AM [2019] 2 IR 115: Confirms that, in exceptional cases, inherent jurisdiction remains available as a constitutional “backstop” and that courts must avoid interweaving or creating parallel statutory tracks. O’Donnell J adopts this respect‑for‑the‑Oireachtas approach: use statutes where they can vindicate rights, resort to the inherent jurisdiction where they cannot.
• Re FD [2015] 1 IR 741: Limits reliance on inherent procedural powers where the Oireachtas has enacted a code. Distinguished here: the Court is exercising inherent subject‑matter jurisdiction to protect constitutional rights, not procedural powers.
• DG v Eastern Health Board [1997] 3 IR 511 and SS v HSE [2008] 1 IR 594: Foundations for using inherent jurisdiction to vindicate constitutional rights where necessary—even in liberty‑restrictive contexts—with robust safeguards. These principles underpin the approach to vulnerable adults.
• HSE v JO’B [2011] 1 IR 794; HSE v VE (2012, unreported); HSE v VF [2014] 3 IR 305: Illustrate inherent jurisdiction used for vulnerable adults where the Mental Health Act 2001 did not apply and statutory mechanisms were inadequate to meet identified needs.
• AC v Cork University Hospital [2019] IESC 73; [2020] 2 IR 38: Sets the test for deprivation of liberty: look at the “concrete situation”; complete supervision/control and not being free to leave equals deprivation of liberty. Applied here to classify “light‑touch” Garda‑return orders as detention in law.
• KK trilogy:
  • KK (No. 1) [2023] IEHC 306 and KK (No. 3) [2023] IEHC 565 (Hyland J): Post‑2015 Act, detention of adults who lack capacity proceeds via inherent jurisdiction, not wardship; capacity must be functionally decision‑specific; 2015 Act principles inform inherent‑jurisdiction proceedings; strong safeguards (representation, voice, proportionality) required.
  • Child and Family Agency v KK; HSE [2024] IECA 242 (Hogan J): The 2015 Act fundamentally changes the legal architecture; detention of adults is not to be done under legacy wardship post‑commencement; s. 4(5) preserves inherent jurisdiction to make orders for care, treatment or detention of persons who lack capacity.
• Martinez Fernandez v Hungary (ECtHR, 27 May 2025): Emphasises effective representation for persons deprived of liberty; representatives must have meaningful contact, explore wishes, seek instructions, and test arguments. O’Donnell J affirms Irish practice: GALs must present the person’s will and preferences and also assist the Court with objective analysis where appropriate.

Legal Reasoning

The Court’s reasoning proceeds in carefully sequenced steps:

• Capacity findings: Adopting the functional, decision‑specific test (consistent with Fitzpatrick v FK and the 2015 Act), the Court accepts unanimous expert evidence that M.T. lacks capacity regarding residence, personal safety/welfare, finances (at least for non‑routine decisions), and contact/internet use. Importantly, the cause of incapacity—profound environmental deprivation and learned maladaptive behaviours—does not limit the Court’s jurisdiction: what matters is the present inability to understand, use, and weigh information relevant to key decisions.
• What amounts to detention: Applying AC v CUH, the power to apprehend and return M.T. to her placement if she absconds is a deprivation of liberty, even if “light‑touch.” Benevolent purpose does not alter its legal character.
• Limits of the 2015 Act:
  • No general deprivation of liberty jurisdiction exists under the 2015 Act (outside narrow Part 10 situations not applicable here);
  • Section 44(1) expressly forbids granting a decision‑making representative the power to prohibit contact with a particular person; and
  • Section 38(2) cannot be read as a carte blanche to do via urgent court order what the Act elsewhere prohibits; “expedient” addresses timing/urgency, not subject‑matter override.
  Therefore, the Act cannot lawfully deliver the specific orders needed here (detention and contact restrictions).
• Inherent jurisdiction, preserved and disciplined: Section 4(5) of the 2015 Act confirms the Oireachtas did not intend to displace the High Court’s inherent jurisdiction to order care, treatment, or detention for persons lacking capacity. However, out of respect for the legislative scheme, the Court will:
  • Resort to inherent jurisdiction only when statutory mechanisms cannot vindicate rights (the “backstop” approach in HSE v AM);
  • Be guided by the 2015 Act’s principles (necessity, proportionality, least restriction, participation, will and preferences);
  • Ensure procedural safeguards: independent representation, the person’s voice is heard, expert evidence, regular reviews, and ongoing necessity assessments (as in KK (No. 3)).
• Proportionality and minimisation of restriction: The Court continues the orders because they are necessary to vindicate M.T.’s rights to life, health, welfare, and dignity, while simultaneously requiring the HSE/GAL to explore technological solutions to enable supervised phone/internet use—signalling constant review to reduce restrictions when safe.
• Single legal route, not parallel tracks: To avoid the mischief of interwoven regimes cautioned against in HSE v AM, the Court keeps all necessary restraints within inherent jurisdiction rather than dividing relief between the inherent jurisdiction (for detention/contact) and the 2015 Act (for other supports). This promotes coherence and clarity.
• GAL role post‑Martinez: The Court affirms that Irish GALs must both relay the person’s will/preferences and test the evidence; they may also assist with an objective appraisal where appropriate. That dual function remains compatible with Strasbourg requirements for effective representation.

Impact

The judgment has significant, immediate, and systemic effects:

• Clear limits to the 2015 Act: Two bright‑line propositions are crystallised:
  • Deprivation of liberty for adults lacking capacity (outside the narrow Part 10 context) cannot be ordered under the 2015 Act; and
  • A decision‑making representative cannot be empowered to prohibit contact (s. 44(1)); s. 38(2) cannot be used to achieve that result by judicial order.
  Where safeguarding requires detention or contact restrictions, the inherent jurisdiction is the only lawful route—subject to rigorous safeguards.
• Functional capacity approach reaffirmed: The Court moves decisively beyond diagnosis labels. Environmental deprivation and trauma‑related maladaptive learning can impair functional capacity to the point that protective measures are necessary.
• Procedural template: The Court adopts and exemplifies the safeguard architecture urged in KK (No. 3):
  • Independent assessment of capacity (decision‑specific) with periodic re‑assessment;
  • Effective representation and the person’s direct participation (letters, attendance, evidence);
  • Regular court reviews and continuous minimisation of restrictions (e.g., explore supervised tech solutions);
  • Integration of 2015 Act guiding principles into inherent‑jurisdiction decision‑making.
• Operational guidance for agencies and practitioners:
  • When care plans require detention or contact prohibition, file under the High Court’s inherent jurisdiction; do not attempt to shoehorn into the 2015 Act;
  • Anticipate a “single route” approach—avoid parallel proceedings in different courts;
  • Build in technological and practical measures to reduce restrictions over time and demonstrate continuous proportionality review;
  • Document the person’s will and preferences and how proposed measures respect/engage with them.
• Policy implication: The case underscores the gap in comprehensive deprivation‑of‑liberty safeguards for adults lacking capacity. It may catalyse legislative consideration of a specific statutory framework (akin to “DoLS” models elsewhere) rather than reliance on case‑by‑case inherent jurisdiction.

Complex Concepts Simplified

• Inherent jurisdiction vs inherent powers: Inherent jurisdiction is the High Court’s constitutional authority to decide matters necessary to vindicate fundamental rights (Article 34/40). Inherent powers are procedural tools all courts use to manage cases. This judgment uses inherent jurisdiction—not mere powers—to protect M.T.’s rights where legislation is insufficient.
• Functional (decision‑specific) capacity: Capacity is not “all or nothing.” A person may have capacity for some decisions but not others. The question is whether the person can understand, retain, use/weigh relevant information and communicate a choice about the specific decision.
• Deprivation of liberty: If a person is under continuous supervision/control and not free to leave, there is a deprivation of liberty—regardless of benevolent aims. A Garda power to return a person to a placement is detention in law, even if the person “usually” goes out freely.
• 2015 Act boundaries:
  • It facilitates decision‑making but does not, in general, authorise detention;
  • A decision‑making representative cannot be empowered to prohibit someone from contacting the relevant person (s. 44(1));
  • Urgent court orders under s. 38(2) do not expand subject‑matter beyond what the Act otherwise allows.
• Learned maladaptive behaviour vs mental illness: A person can lack capacity because their life experience has deprived them of chances to learn essential living skills, even without mental disorder. Here, M.T. has average intellect but extremely low adaptive functioning; her capacity deficits are real and legally significant.
• “Light‑touch” orders are still detention: Where Gardaí may return a person who absconds, the order is detention, irrespective of how infrequently it is invoked.
• GAL’s role after Martinez Fernandez: A GAL must (a) actively engage with and represent the person’s will and preferences and (b) ensure the case against the person is properly tested; they may also provide an objective appraisal for the Court when appropriate.
• Proportionality/minimisation: Any restriction must be necessary, proportionate to the risks, the least restrictive available, and kept under regular review with a view to reduction—e.g., exploring monitored tech that allows safe communication.

Conclusion

HSE v M.T. is a careful and consequential judgment that both protects a vulnerable adult and clarifies the post‑2015 Act legal landscape. It establishes, with welcome precision, that:

• Detention and prohibitions on contact cannot be ordered under the 2015 Act (save for narrow circumstances not applicable here);
• Section 44(1) draws a bright line against empowering representatives to ban contact; section 38(2) cannot be used to circumvent that line;
• Where such measures are necessary and proportionate to vindicate constitutional rights, the High Court must act under its inherent jurisdiction preserved by s. 4(5);
• The 2015 Act’s guiding principles should nonetheless inform the Court’s approach and the design of safeguards; and
• Capacity analysis is decision‑specific, and environmental deprivation can (and did) produce profound functional incapacity justifying protective intervention.

Practically, the judgment provides a pathway and a set of guardrails: use the inherent jurisdiction sparingly, design the least restrictive measures, audit necessity continuously, hear the person’s voice, and avoid interweaving jurisdictions. Systemically, it illuminates a gap in statutory deprivation‑of‑liberty safeguards for adults lacking capacity and may prompt legislative attention. In the meantime, M.T. will continue to live—and to flourish—under a court‑supervised regime that aims not to constrain her permanently, but to scaffold her autonomy until she can truly exercise it.